NEW YORK — The close ties between Canada and the United States have evolved and strengthened since the terrorist attacks of Sept. 11, 2001, as Canadians have heeded the concerns of their American neighbours, Defence Minister Peter MacKay said Friday.

“As we all know, even the closest relationships need care, nurturing and constant attention,” MacKay told a conference commemorating the 10th anniversary of 9-11.

“Since 2001, we have been paying particular attention to the concerns, challenges, fears and expectations of our closest friend — the United States,” MacKay said in prepared remarks for his speech.

As Canada and the U.S. have worked side by side around the world post-911 — particularly in Afghanistan and more recently, in Libya — the two countries have been working hard “to strengthen our security partnership here at home,” he said.

Discussions on a border perimeter security agreement are ongoing, he added, and are “very productive.” An announcement on the so-called Beyond the Border initiatives is expected sometime this fall.

“While the decade since 9-11 may have brought our security efforts closer together, there has also been a sense that, in terms of trade and travel, we have risked creating a barrier between us,” he said.

MacKay said the new initiatives will help officials in both countries identify and address threats early by improving screening procedures of individuals and cargo entering North America, as well as enhancing cross-border law enforcement.

“At the same time, it will facilitate trade, movement, the creation of jobs and economic growth throughout the continent,” he said.

The conference, hosted by the non-profit Foreign Policy Association, was held in the city hardest hit by the terrorist attacks 10 years ago. More than 3,000 people perished when terrorists flew fuel-engorged jetliners into the World Trade Center towers in New York and the Pentagon in Washington, in a shocking day that stunned the world and changed the course of contemporary geo-politics.

MacKay’s visit came a day before his boss is scheduled to arrive. Prime Minister Stephen Harper is travelling to New York this weekend to take part in commemoration ceremonies.

Harper will join a public memorial service on Sunday in lower Manhattan. “On this day, we will pay tribute to Canadians, Americans and all those who lost their lives nearly 10 years ago in these heinous attacks,” Harper said in a statement Friday.

“As we pay tribute to the victims and their loved ones, we also honour members of the military, law enforcement and intelligence personnel who continue to fight on the front lines against all forms of terrorism.”

The evening before, the prime minister will meet privately with the families of Canadians killed in the attacks. Harper will show his support for those affected by “the senseless and tragic attacks,” said the statement issued by the prime minister’s office.

Canadians have been celebrated in the United States this week for their roles in helping Americans endure that terrible day 10 years ago and those that followed.

The Newfoundland town of Gander received an international resiliency award at a day-long event in Washington for opening its heart, and its homes, to thousands of people stranded there after flights were grounded on 9-11.

The outpouring of American gratitude and affection for Canada on the anniversary is an antidote to the tensions that developed in the relationship after the 2001 attacks.

American citizens and legislators alike believed for years that the terrorists had entered the U.S. through Canada, a myth that still persists.

They were critical of Canadian immigration policies and feared Canada’s border was a porous one. Border security measures were beefed up to such an extent that exporters on both sides of the boundary complained that trade and commerce was significantly hindered.

MacKay didn’t touch on those tensions in his speech, focusing instead on the closeness of the friendship and the efforts made, post-9-11, to work with Americans to secure the border.

“It is a friendship and a partnership that, I believe, is recognized around the world for its depth, strength, breadth and resilience,” MacKay said.

“Indeed, since 9-11, we have seen a further deepening of the shared vision of security for our continent because our values are shared, because our security is inherently linked and because we are the closest of friends and partners.”